More Park Facilities Reopen During May 2013
Watch Hill and Sailors Haven marinas open May 10. Limited ferry service from Sayville to Sailors Haven resumes May 13 and ferries from Patchogue to Watch Hill start on May 18. Remaining park facilities to reopen by May 25, 2013. More »
Despite its common name, the horseshoe crab (Limulus polyphemus), is more closely related to spiders and scorpions than crabs. All are invertebrates from the phylum Arthropoda, or arthropods. This group of animals includes insects (Insecta); spiders, scorpions, ticks and mites (Arachnida, or arachnids); crabs, lobsters, shrimp and barnacles (Crustacea, or crustaceans); and the 4 world-wide species of horseshoe crabs (Merostomata). (Find out more!)
Horseshoe crabs are an ancient species. For over 300 million years (at least 100 million years before there were dinosaurs on earth) horseshoe crabs have roamed the world's oceans and and look today much as they have through the millennia.
Fun Horseshoe Crab Facts
Did you know that horseshoe crabs have blue blood? The protein (hemocyanin) that carries oxygen in horseshoe crab blood contains copper. When oxygen binds to the copper, the blood turns blue. As the oxygen is removed from the copper (as the blood circulates and delivers oxygen to the tissues of the horseshoe crab) the blood becomes colorless. The protein (hemoglobin) that carries oxygen in human blood contains iron. When oxygen is bound to the iron, human blood is red. As the oxygen is removed from the iron, the blood becomes blue.
The name horseshoe crab refers to the shape of the animal. The front half of a horseshoe crab looks like a horse's hoof or a horseshoe.
For More Information
Did You Know?
In the mid-1970s, Fire Island's deer herd consisted of only about 50 white-tailed deer. By 2005, the number was estimated to be 500-700 deer. More...